To limit the emissions of pollutants of internal combustion engines, in particular in motor vehicles, catalytic converters and/or particle filters or the like have long been used for purifying the exhaust gas. In order for catalytically assisted conversion of the pollutants to occur, the exhaust gas and/or the catalytic converter or the particle filter must be at a predefined minimum temperature. In particular after a cold start or restart of the internal combustion engine, it is often the case that such a minimum temperature has not yet been reached. It is therefore sought to increase the temperature of the exhaust gas and/or of the catalytic converter or particle filter by way of electrically operated heating elements.
For example, EP-B1-0783621 has disclosed an electrically heatable catalytic converter which is formed with two honeycomb bodies. The first honeycomb body is in this case connected to an electrical voltage source, and may be flowed through by current. Owing to the ohmic resistance heating, the sheet metal foils of the first honeycomb body are then significantly heated, wherein the catalytic coating, which is in contact therewith, of the first honeycomb body and/or the exhaust gas flowing through the first honeycomb body is heated. For stability reasons, it is furthermore provided that the first honeycomb body is supported by way of pins and holding elements against a second honeycomb body arranged downstream. Furthermore, the pins and holding elements are suitable for electrically insulating the two honeycomb bodies with respect to one another. Such an embodiment of an electrically heatable catalytic converter is already well proven, but still requires relatively high outlay for production.
The connection of two honeycomb bodies by way of pins is generally realized such that the pins engage both into a cavity of the first honeycomb body and into a directly oppositely situated cavity of the second honeycomb body. The production of the connection has however proven to be relatively difficult, because it is difficult to achieve an aligned and/or parallel orientation of the cavities of adjacent honeycomb bodies. This is the case in particular when the honeycomb bodies are formed from wound sheet-metal layers, and the exact positioning of the cavities after the winding cannot be accurately predicted and/or set, giving rise to increased production costs and a relatively long assembly duration.